Reminder for people keeping specimens of animals/bugs. Beware of dermestid beetles (dermestes maculatus). Dermestid beetles are an important part of the natural process, since they feed on the decomposing flesh of animals and other bugs. However, if you intend to preserve a specimen, you need to watch out for these little guys.
Here are a few ways that you can prevent dermestid beetles from feeding on your specimens:
1. If you are preserving a specimen yourself, make sure you are removing the majority of internal organs so your specimen does not rot. Dermestid beetles feed on rotting bodies, so as long as you take measures to keep the body from rotting, dermestid beetles will be less likely to feed. This is mainly aimed toward specimens like frogs, birds, bats, anything with large organs. You can usually skip this step if you are preserving small beetles or butterflies, but even some larger bugs like giant katydids need to be cut open and their insides need to be removed. If the removal of the internal organs drastically changes the shape of the specimen’s body, you can stuff the body with cotton and glue the seam shut to keep the shape.
2. If you have a specimen with a large body, but not large enough to cut into, you can inject the body with alcohol. Much like preserving a wet specimen, injecting alcohol into the body of a specimen will help prevent remaining tissue and organs from rotting, and will also help keep your specimen in its pose. However, depending on the size and softness of your specimen, alcohol may not be a long term solution to rotting. Alcohol may need to be re-administered later on to ensure dermestid beetles don’t try to eat the specimen.
3. Freeze your specimens. Dermestid beetles will die after being frozen, so if it so happens that a dermestid beetle or its eggs/larvae have unwarrantedly made a home among your specimen, freezing them for 3-4 days will kill the dermestid beetles. It is always a good idea to routinely freeze your specimens, even if they look clean and untouched. An ounce of prevention.
The photos at the beginning of this post are of one of my luna moths that unfortunately started being fed on by a dermestid beetle. This is the damage of only one beetle, so I’m sure you can imagine what a group of them could do. Please watch out for your specimens, and do what you can to ensure they are properly maintained! Not only for the specimen itself, but also for your own safety. Decomposing animals are a biohazard, and may be a threat to your health.